Missed OG, Should I fix it? Pumpkin Ale

[LostDogBeer]

This is my 5th batch and one that I (more or less) concocted my own recipe to make. Using the BrewersFriend.com web site it's supposed to have an OG of 1.045 for 5.5 gallon batch but I only could get it to 1.040. Is that too big of a gap to deal with? If so, is there anyway to fix it? I just put the batch into primary about 6 hours ago. here's the recipe I used:

HOME BREW RECIPE:
Title: LostDog Pumpkin ale

Brew Method: Extract
Style Name: Holiday/Winter Special Spiced Beer
Boil Time: 60 min
Batch Size: 5.5 gallons (fermentor volume)
Boil Size: 2.5 gallons
Boil Gravity: 1.098
Efficiency: 35% (steeping grains only)

STATS:
Original Gravity: 1.045
Final Gravity: 1.012
ABV (standard): 4.21%
IBU (tinseth): 12.11
SRM (morey): 8.8

FERMENTABLES:
6 lb - Liquid Malt Extract - Amber (80%)
8 oz - Brown Sugar (6.7%)

STEEPING GRAINS:
8 oz - German - Carapils (6.7%)
8 oz - American - Caramel / Crystal 10L (6.7%)

HOPS:
1 oz - Mount Hood, Type: Pellet, AA: 4.8, Use: Boil for 60 min, IBU: 10.78
1 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 2 min, IBU: 1.33

OTHER INGREDIENTS:
30 oz - Pumpkin, Time: 5 min, Type: Other, Use: Boil
1 tsp - Pumpkin Spice, Time: 2 min, Type: Spice, Use: Boil

YEAST:
Fermentis / Safale - American Ale Yeast US-05
Starter: Yes
Form: Dry
Attenuation (avg): 72%
Flocculation: Medium
Optimum Temp: 59 - 75 F
Fermentation Temp: 68 F

Generated by Brewer's Friend - http://www.brewersfriend.com/
Date: 2013-09-09 23:30 UTC
Recipe Last Updated: 2013-09-09 23:28 UTC

 

[flars]

Were you able, with certainty, to get the boiled wort and top off water 100% mixed so there will not be layers of differing concentrations?

 

[LostDogBeer]

Yes, I think so. I shook the heck out of it to aerate it just before pitching the yeast. It's was definitely good and mixed before I used the thief to get grab some wort for hydrometer reading.

 

[Demus]

It must not have mixed; the extract and sugar alone should have got you to 1.042, and that's without the steeped grains. I bet you got to 1.045 and just drew a thin sample. Next time, get an extra bucket and dump the entire batch with top off water back and forth 2 or 3 time before putting it in the carboy. This will ensure it's mixed AND aerated...

 

[LostDogBeer]

Demus,
That's interesting. I would have thought that the 3 minutes of rocking the carboy back and forth would have shaken the contents well enough. You're saying to move the wort between buckets to get a full mix? Sounds like a huge mess but I'll try it next time.

 

[Demus]

Think of it this way. Do you drink coffee? When you put a few spoons of sugar in what do you do next? Do you think rocking the cup back and forth for a few minutes would mix it or be bitter on top and sweet on the bottom?
The best solution is to boil the full volume, but of course that requires a bigger pot and more issues getting it chilled down. Till then, find a better way to mix it up! Welcome to brewing!!!

 

[boydster]

Do you know for sure you hit your target volume of water? If you got the right amount of water into the fermenter, you can rest assured you hit your target gravity. Even if you don't mix your top off water very well, the yeast will mix it for you during fermentation.

The extract and sugar have a predetermined amount of fermentable sugar, and adding that to a predetermined amount of water will give to you a mathematically calculable OG - in other words, efficiency really isn't an issue to concern yourself with in extract brewing.

 

[Demus]

Do you know for sure you hit your target volume of water? If you got the right amount of water into the fermenter, you can rest assured you hit your target gravity. Even if you don't mix your top off water very well, the yeast will mix it for you during fermentation.

The extract and sugar have a predetermined amount of fermentable sugar, and adding that to a predetermined amount of water will give to you a mathematically calculable OG - in other words, efficiency really isn't an issue to concern yourself with in extract brewing.

Agreed. I'd also add though if you didn't mix it up enough to get a proper gravity reading, it's very unlikely that it was adequately aerated...

The common rocking of the carboy method is akin to driving nails with chopsticks...

 

[boydster]

You're right about rocking not being a very effective way to aerate. Dumping from bucket to bucket certainly will do that. Also pouring through a fine mesh to filter out hops debris and break material will aerate, but if done before adding top off water you will still have some stratification. My point is simply that if you'd rather not dump between multiple buckets (5 gallons is kinda heavy...), you can still aerate it just fine in ways that may already be part of your process, and again, since you are adding a measured amount of sugars to a measured amount of water, you will hit your target gravity.